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View Full Version : Is my 8xl bad ??



Philmunsterman
02-13-2010, 02:40 PM
I'm having problems with my 8xl when I try and run it on 4S it cuts out at around 1/4 throtle. Also I can just spin the shaft by hand with almost no resistance. It might have gotten hot the last time I ran it. How do I know if the motor is bad ? Thanks Phil

Fluid
02-13-2010, 02:52 PM
Well, a brand new 540/8XL has very little resistance to turning the shaft by hand, so that tells us nothing. And you are not confessing to your parents here - did it get hot or not? How hot? Over-temping a Feiago can damage the magnets and/or windings, either of which could cause your symptoms. But really, it sounds a little more like an ESC issue at this point, or poor connections between the ESC and the motor.

Tell us more about your setup - cells, ESC, boat, prop, radio, how did it run before, what has changed since then, etc.

The only reliable way for the hobbyist to tell if his motor is bad is to compare it to a known good motor.



.

Philmunsterman
02-13-2010, 03:01 PM
Good points. I'm running a new etti 150. Rechecked all connections (seem good). 160 to 170 by the time I checked it. It dose run fine on 2S ??? I don't have another motor to swap in.

Jeepers
02-13-2010, 05:33 PM
to repeat Fluid you did not tell us what set up your running, (except for the ETTI 150 and an 8XL) what type of boat are you running, how many cells, what type of cells, what size of prop.

Steven Vaccaro
02-13-2010, 05:50 PM
The only way I've found to check for mag damage is to remove the rotor. If you remove it and place it next to some steel, you will find an incredibly strong magnetic force. If its been overheat to failure, it will have a slight attraction. Its not a scientific method, but it works.

Philmunsterman
02-13-2010, 06:06 PM
Jeepers, In the first post it says it's on 4S. Hull and prop shouldn't matter, this is happening on the bench.

Thanks Steven I might try that.

egneg
02-13-2010, 06:45 PM
Does the motor stutter as if it is single phasing? I had a similar problem and it was due to a solder joint of a connector between the esc and motor. You need to cut off the heat shrink and give each a good wiggle and tug.

Philmunsterman
02-13-2010, 07:03 PM
I think I'm going to re-solder the connections between the esc and motor.

domwilson
02-13-2010, 07:43 PM
I seem to recall another poster who had a similar problem. He just reprogrammed the Etti and that took care of the issue. Might try that. It's the easiest thing to do.

Flying Scotsman
02-13-2010, 08:50 PM
I'm having problems with my 8xl when I try and run it on 4S it cuts out at around 1/4 throtle. Also I can just spin the shaft by hand with almost no resistance. It might have gotten hot the last time I ran it. How do I know if the motor is bad ? Thanks Phil

You state in another post that the last time you ran the motor the temps were 160 to 170 F. Is this a new motor?....those temps are high. Bench testing a new or used motor at full throttle is not a good idea, for a second or two is OK. Sounds like the motor is toast.

Douggie